Recently it was time to clean the PLUS Countertop filter we use in the office. It had been a few months and you could tell the flow rate was dropping a bit. One of the perks of ceramic is you can scrub off all the junk it catches and bring it's flow rate back to life, while also keeping the filtration at high levels.
Our office has a municipal source water, medium hardness, with a normal blend of treatment chemicals like chloramine and fluoride and then some agricultural runoff to finish it off.
Nothing too bad. (sarc)
But this time we grabbed a pic to compare what a filter looks like after some use. It's a startling difference. A new cartridge is on the left, the used one on the right. Covered in a nice brown layer of slime and grit.
There's an old saying if you don't have a filter, you are the filter. Nothing makes that point more clearly than our ceramics.